I think even Paul clarified there is one Gospel and it was taught by all the disciples and apostles.
1 Corinthians 15:1-8 NASB
Now I make known to you, brethren, the gospel which I preached to you, which also you received, in which also you stand, by which also you are saved, if you hold fast the word which I preached to you, unless you believed in vain.
For I delivered to you as of first importance what I also received, that Christ died for our sins according to the Scriptures, and that He was buried, and that He was raised on the third day according to the Scriptures, and that He appeared to Cephas, then to the twelve.
After that He appeared to more than five hundred brethren at one time, most of whom remain until now, but some have fallen asleep; then He appeared to James, then to all the apostles; and last of all, as to one untimely born, He appeared to me also.
If you read my exchanges with the others who believe that Paul is a shady character, you will notice one thing in common — THEY DON’T ACCEPT PAUL’s epistles.
Therefore, anything he says about himself ( say, the epistle to the Galatians or his letter to the Corinthians ) is suspect to these people.
Which is to say, they pick and choose what part of the New Testament they will accept as God’s word.
THAT is exactly what got the PCUSA into this situation (i.e. accepting gay marriage )